B2705

DTC B2705

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.

DTC Descriptor
DTC B2705 02
- Gearshift Unlock Circuit Short to Ground

Diagnostic Fault Information





Circuit/System Description

The body control module (BCM) controls the automatic transmission shift lock control solenoid by providing a battery positive voltage to the solenoid. The BCM utilizes a smart driver to control the voltage supply circuit to the automatic transmission shift lock control solenoid. The smart driver monitors the voltage and current flow of the control circuit.

Conditions for Running the DTC

* The ignition switch is in the ON position.
* The brake pedal is pressed.
* The transmission is in the PARK position.

Conditions for Setting the DTC

Sets if there is a short to ground in the automatic transmission shift lock control solenoid control circuit.

Action Taken When the DTC Sets

The BCM will not attempt to enable the voltage supply circuit of the automatic transmission shift lock control solenoid until the next key cycle.

Conditions for Clearing the DTC

* A current DTC will clear when the malfunction is no longer present and the ignition switch is cycled.
* All BCM history codes will clear after 100 ignition cycles with no current codes active during the 100 ignition cycles.

Reference Information
Schematic Reference

Shift Lock Control Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Automatic Transmission Shift Lock Control Description and Operation (Floor Shift) (Automatic Transmission Shift Lock Control Description and Operation (Floor Shift))Automatic Transmission Shift Lock Control Description and Operation (Column Shift) (Automatic Transmission Shift Lock Control Description and Operation (Column Shift))
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information

Circuit/System Verification

1. Ignition ON, clear the DTC. Observe the scan tool BCM Brake Applied Output Signal parameter. The parameter should change from ON to OFF when the brake pedal is depressed.

• If the parameter does not change, refer to Stop Lamps Malfunction (Stop Lamps Malfunction).

2. Ignition ON, observe the scan tool BCM Shifter Unlock Command parameter. The parameter should change from ON to OFF when the brake pedal is depressed.

• If the parameter does not change, replace the BCM.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the shift lock control solenoid.
2. Ignition OFF, test for less than 30 ohm between the appropriate connector terminal listed below and ground:

* Floor shift - terminal A
* Column shift - terminal B

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Install a test lamp between connector terminal A and terminal B.
4. Ignition ON, command the scan tool BCM Shift Lock Solenoid output control ON and OFF. The test lamp should turn ON and OFF as commanded.

• If the test lamp is always ON, test the control circuit for short to voltage. If the circuit tests normal, replace the BCM.
• If the test lamp is always OFF, test the control circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If the circuit tests normal, test or replace the shift lock control solenoid.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Transmission Control Replacement (4T65-E - Automatic Transmission)
* Control Module References (Programming and Relearning)for BCM replacement, setup, and programming